MAGNETISM 



The figure shows a typical arch, with a bright curtain 

 beneath it, witnessed on June 19, 1908. 



Searchlight Aurora. — Long bright expanding 

 beams suggest a resemblance to searchlights, not only by 

 their form, but by the rapidity of their movements. They 

 swing about in the same manner, and shoot out suddenly 

 from the horizon or from a patch of nebulous aurora, and 

 as suddenly disa]3pear. They often accompany other 



Arch and Curtain, June 19 



forms of aurora. Some searchlight beams are shown in 

 the figure of the very peculiar aurora of May 23, 1908. 



Nebulous Aurora. — ^A nebulous auroral haze is con- 

 stantly associated with clouds, occurring on the upper sur- 

 face and showing at the edges. Sometimes the nebulous 

 light accompanied haze so thin that it would not be seen 

 without the illumination, and in such cases it might be seen 

 drifting along with the wind. 



Other Auror^e. — ^All the definite types of auroree 



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